ChIP-validated antibodies to histones and histone modifications. Histone post-translational modifications (PTMs) are important regulators of chromatin structure and function. Some of the more widely studied PTMs include acetylation, arginine methylation, lysine methylation, phosphorylation, SUMOylation and ubiquitylation. Specific histone PTMs recruit modification binding “effector” or reader proteins, conferring a unique function or identity to regions of the genome enriched for the modified histone. ChIP-validated antibodies recognizing these modifications in their specific protein sequence context are important tools for studying the role of histone PTMs in a variety of cellular processes, such the regulation of gene expression, DNA damage repair and the maintenance of chromatin structure.